Single and multiple optical lens array fiber optic transceiver devices require precise optical component to fiber alignment for optimal function. The devices may include optical laser and/or photodetector components each coupled to a distinct optical fiber component through an optical lens component. The alignment process generally involves adjusting a laser light beam path from an optical fiber or laser to a receiving photodetector or optical fiber element, respectively. The typical optical alignment tolerance for a 62.5 micron diameter fiber using a lens array is on the order of only plus or minus 5 microns. Thus, alignment considerations are essential in the design and assembly of fiber optic transceiver devices.
At least two methods are known for aligning the transceiver optical components and fiber optic cable. A first method is known as active alignment. Active alignment utilizes the laser in an active state at a sub-assembled stage of the transceiver. After the laser is turned on, the optical components are moved in a relative radial plane (normal to the optical path) while a photoreceiver output is monitored to establish maximum light throughput. Once the light throughput is optimized, the components are mechanically fixed to hold them in alignment. A second method is known as passive alignment. Passive alignment relies on holding very accurate mechanical tolerances on all elements affecting the optical path, and alignment is therefore achieved without monitoring laser output.
One consideration in the design of the fiber optic transceiver involves mounting the optical lens array within the transceiver. The design should provide precise positioning of the optical lens array thereby facilitating optical transceiver alignment. The precise alignment of the lens array is a critical element in the passive alignment of the transceiver. Another design consideration involves complexity of the optical lens array mounting. The design should provide a simple, compact assembly containing a small number of parts. Moreover, the optical lens array should be mounted with a relatively simple, cost-effective strategy ensuring easy manufacture and alignment process. Current strategies, however, may not provide a simple, inexpensive, and accurate optical lens array mounting strategy.
Therefore, it would be desirable to provide an assembly and method for mounting an optical lens array in a fiber optic transceiver that would overcome the aforementioned and other disadvantages.